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Home >> Lexus >> 2008 >> SC 430 >> Repair and Diagnosis >> External Pages >> Different car >> Section 33 (Audio/Visual) >> Audio And Visual System >> Steering Pad Switch Circuit >> Inspection Procedure
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Inspection Procedure

WARNING: This page is about a different car, the 2007 Lexus SC 430. However, it is still accessible from the selected car via links, so may be relevant.
  1. READ VALUE OF INTELLIGENT TESTER (STEERING PAD SWITCH MODULATOR) 
    1. Check the DATA LIST for proper functioning of the steering pad switch.

      Steering pad switch modulator: 

      DATA LIST

      Item Measurement Item / Display (Range) Normal Condition Diagnostic Note
      AV MODE SW Audio mode switch / ON or OFF ON: Audio mode switch is pushed
      OFF: Audio mode switch is not pushed
      -
      AV VOL UP SW Audio volume UP switch / ON or OFF ON: Audio volume UP switch is pushed
      OFF: Audio volume UP switch is not pushed
      -
      AV VOL DOWN SW Audio volume DOWN switch / ON or OFF ON: Audio volume DOWN switch is pushed
      OFF: Audio volume DOWN switch is not pushed
      -
      AV SEL UP SW Audio selector UP switch / ON or OFF ON: Audio selector UP switch is pushed
      OFF: Audio selector UP switch is not pushed
      -
      AV SEL DOWN SW Audio selector DOWN switch / ON or OFF ON: Audio selector DOWN switch is pushed
      OFF: Audio selector DOWN switch is not pushed
      -
      AV VOL SET SW Audio volume set switch / ON or OFF ON: Audio volume set switch is pushed
      OFF: Audio volume set switch is not pushed
      -
      VOICE HOOK SW* Speech recognition hook switch / ON or OFF ON: Speech recognition hook switch is pushed
      OFF: Speech recognition hook switch is not pushed
      -
      HINT:
      *: w/ Navigation System

      OK: 

      ON appears on the screen when each steering pad switch is pushed. 

    OK: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE 

    NG: Go to next step 

  2. REPLACE STEERING PAD SWITCH MODULATOR 
    1. Replace steering pad switch.
    2. Check if the vehicle is equipped with a navigation system.

      Result 

      RESULT CHART

      Result Proceed to
      w/ Navigation system A
      w/o Navigation system B

    B: END 

    A: Go to next step 

  3. RESET STEERING PAD SWITCH MODULATOR 
    1. The following procedure must be completed within 30 seconds:
      1. Turn the ignition switch to ACC.
      2. Press the "Mode" button for at least 10 seconds.
      3. Within 5 seconds, press channel up twice and channel down twice.

    NEXT: END